code: def download(url, filename):
      if not os.path.exists("data"):
          os.makedirs("data")
      out_file = os.path.join("data", filename)
      if not os.path.isfile(out_file):
          urlretrieve(url, out_file)
  
file_path: autograd/examples/data_mnist.py
imports: from __future__ import absolute_import
  from __future__ import print_function
  import sys
  import os
  import gzip
  import struct
  import array
  import numpy
  from urllib.request import urlretrieve
label_desc: Use image node_id 1 for calling a global function with example usage: download(url, filename) without return types